In ink jet printing it is sometimes required that the nozzle array be adhered to the polymer which forms the ink chambers on the print head chip. The nozzle array can be gold plated, making it very difficult for the polymer to adhere to it with a durable bond, because the bond tends to degrade in the presence of aqueous ink. This degradation leads to severe reliability problems. In the prior art, the bond has been formed by using heat and pressure, but such a bond is mechanical in nature and it is therefore relatively easy for moisture ingress to occur at the interface and weaken the bond.
U.S. Pat. No. 3,725,719 deals with a method and apparatus for inhibiting gaseous permeation and corrosion of materials by using a coating of gold and tantalum and also an organic coating. The patent is obviously not dealing with ink jet printing.
U.S. Pat. No. 4,608,268 and related U.S. Pat. No. 4,668,336 both deal with a process for making a mask used in x-ray photolithography. It shows layers of tantalum, gold and polyimide. The patents, however, are in no way concerned with ink jet printing.